ABB REB670 Applications Manual page 305
Busbar protection 2.1 ansi, relion 670 series
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Also See for REB670:
- Applications manual (554 pages) ,
- Commissioning manual (196 pages) ,
- Operator's manual (116 pages)
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1MRK 505 337-UUS -
Application manual
thus not permitted until the synchrocheck situation has remained constant throughout the
set delay setting time. Manual closing is normally under more stable conditions and a
longer operation time delay setting is needed, where the tSCM setting is used. During auto-
reclosing, a shorter operation time delay setting is preferable, where the tSCA setting is
used. A typical value for tSCM can be 1 second and a typical value for tSCA can be 0.1
seconds.
Energizingcheck settings
AutoEnerg and ManEnerg
Two different settings can be used for automatic and manual closing of the circuit breaker.
The settings for each of them are:
•
Disabled, the energizing function is disabled.
•
DLLB, Dead Line Live Bus, the line voltage is below set value of VDeadLineEnerg
and the bus voltage is above set value of VLIveBusEnerg.
•
DBLL, Dead Bus Live Line, the bus voltage is below set value of VDeadBusEnerg
and the line voltage is above set value of VLiveLineEnerg.
•
Both, energizing can be done in both directions, DLLB or DBLL.
ManEnergDBDL
If the parameter is set to Enabled, manual closing is also enabled when both line voltage
and bus voltage are below VDeadLineEnerg and VDeadBusEnerg respectively, and
ManEnerg is set to DLLB, DBLL or Both.
VLiveBusEnerg and VLiveLineEnerg
The voltage level settings must be chosen in relation to the bus or line network voltage.
The threshold voltages VLiveBusEnerg and VLiveLineEnerg have to be set lower than the
value at which the network is considered to be energized. A typical value can be 80% of
the base voltages.
VDeadBusEnerg and VDeadLineEnerg
The threshold voltages VDeadBusEnerg and VDeadLineEnerg, have to be set to a value
greater than the value where the network is considered not to be energized. A typical value
can be 40% of the base voltages.
A disconnected line can have a considerable potential due to, for instance,
induction from a line running in parallel, or by being fed via the
extinguishing capacitors in the circuit breakers. This voltage can be as
high as 30% or more of the base line voltage.
Section 12
Control
299
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